Deleterious effects of <i>yacF</i> deletion can be fixed by inhibiting cell elongation.

<p>A) Scanning electron microscopy images showing similar morphology (coccus) of <i>N</i>. <i>elongata</i> Δ<i>mreBCD</i>,<i>pbpX</i>,<i>rodA</i> and the double mutant Δ<i>yacF</i> Δ<i>mreBCD</i>,<i>pbpX</i>,<i>rodA</i>. B) Same reverse-phase HPLC profile of muropeptides after mutanolysin digestion of purified insoluble PG of <i>N</i>. <i>elongata</i> Δ<i>mreBCD</i>,<i>pbpX</i>,<i>rodA</i> and the double mutant Δ<i>yacF</i> Δ<i>mreBCD</i>,<i>pbpX</i>,<i>rodA</i>. C) Similar ratio of GM4 quantity over GM5, GM4-GM3 over GM5-GM3 and finally GM4-GM4 over GM5-GM4 in the PG of Δ<i>mreBCD</i>,<i>pbpX</i>,<i>rodA</i> and the double mutant Δ<i>yacF</i> Δ<i>mreBCD</i>,<i>pbpX</i>,<i>rodA</i>. The raw quantification can be found in <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1005338#pgen.1005338.s002" target="_blank">S2 Fig</a> for <i>N</i>. <i>elongata</i> and the corresponding mutants. The ratio of wild type bacteria, the single mutant Δ<i>yacF</i> and the complemented strain Δ<i>yacF+yacF</i> are also presented. The increased proportion of GM5 in the PG of Δ<i>yacF</i> (as shown in <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1005338#pgen.1005338.g003" target="_blank">Fig 3</a>) can be again observed but this increase is less important than when the <i>mreBCD</i>,<i>pbpX</i>,<i>rodA</i> locus, encoding for the elongation machinery, is deleted. (*** p≤0.001; ** p≤0.01; * p≤0.05 compare to wild-type).